You know, the only effective way I could see associating Head temperature is to have some sort of remote sending unit from the head to a device that would warn you when its to hot (for whatever max temp it may be.)

I just don't see how you can effectively know when the engine is to hot. What are you going to do, run it on the ground until its to hot, then shut it down to cool off, then fly it. How can you know when its to hot unless its already in the air? I know what its like to have an engine overheat since I have done it several times and every engine reacted the same which was a loss of power and either deadsticked in or the throttle was wide open and i came in at an idle.

It doesn't matter who has come up with numbers, your not going to know if your their yet until its too late.